Towns may have to be abandoned due to floods with millions more homes in Great Britain at risk | Environment

Millions more homes in England, Scotland and Wales are facing devastating floods, and some towns may have to be abandoned as climate change renders many areas uninsurable, according to a Guardian investigation.

New analysis of the insurance sector, seen by the Guardian, reveals the scale of concerns in the sector, with bosses warning that large swaths of housing and commercial properties in densely populated areas will be more at risk.

Separately, experts said some towns may have to be abandoned as homes and businesses struggle to obtain insurance in areas regularly hit by storms and rising sea levels.

Densely populated areas, including London, Manchester and parts of north-east England, are likely to be worst affected. Experts also say London’s flood defenses need to be urgently updated to protect the capital from devastating floods.

“The results are grim,” said Jason Storah, managing director of UK and Ireland general insurance at Aviva, which published the analysis. “Millions more properties will be at risk of flooding, with rising temperatures, increased urbanization and inadequate drainage. »

Tenbury Wells, a market town in Worcestershire, has become the first in the country to find that its public buildings are uninsurable. The city has historically suffered devastating floods about once a decade, but in the past six years, residents have been affected four times.

“We feel abandoned,” said Lesley Davies, deputy mayor of Tenbury Council. “We are the model of what could happen in the future – other towns may find themselves in this situation, there are many vulnerable riverside towns everywhere. »

Aviva’s report highlights growing concern within the insurance industry about the impact of extreme weather events driven by the climate crisis.

Storah said: “We’re not talking about this because we’re waving a flag about climate or sustainability – that has nothing to do with it, our business is totally linked to what’s happening in the environment… we’re in the boat and we can’t avoid it. »

Aviva analyzed every parliamentary constituency in England, Scotland and Wales to assess their vulnerability to flooding. In England, the study found the number of properties at risk of flooding is expected to rise by more than a quarter (27%), from 6.3 million to 8 million, and the number of properties located in areas at high risk of flash flooding – which are harder to predict and protect against – is expected to increase by up to 66% by mid-century.

He also found:

• Every constituency in Britain is predicted to face increased flood risk in the future. In England, 69% of constituencies are likely to see an increase of more than 25% in the number of properties facing flood risk by mid-century. In Wales and Scotland, each region is expected to see a similar increase, with many affected far more.

• Bermondsey and Old Southwark in London and Boston and Skegness in Lincolnshire are expected to have around 90% of homes at risk from river and coastal flooding by 2050 – the highest proportions in the country.

• Overall, London and Yorkshire and the Humber collectively account for more than half of the top 20 constituencies affected by river and coastal flooding, highlighting that the east of England could be worst affected.

• The risk of surface water flooding is likely to be particularly acute in dense urban areas, with 14 London constituencies ranked in the top 20.

• Bournemouth East has the highest predicted increase in surface water flooding risk, with its low-lying topography and inadequate drainage making it particularly vulnerable.

• Over the last decade, 110,000 new homes have been built in areas most at risk of flooding, which equates to one in 13 new homes built. Aviva calculates that if this trend were to continue, 115,000 of the government’s planned 1.5 million new homes would also be in areas most at risk of flooding.

Speaking to the Guardian, Emma Boyd, former chair of the Environment Agency, said it may be too expensive to build the flood defenses needed to save some areas.

She added that some of them may have to be abandoned because protecting homes and businesses becomes too expensive. “I think when money is tight, resources are tight, some of these very difficult decisions will have to be made by government to make sure that the money available for flood prevention has the most impact given the budget constraints, but it’s a very difficult policy decision for our leaders to make,” she said.

Boyd warned that London was also at high risk and the government should urgently work to improve current defences.

“Many people think they are protected because of the Thames Barrier and the range of different mechanisms along the sea walls which protect London from rising sea levels and river flooding. [but] a major project needs to be carried out in terms of funding, raising the sea wall along the Thames and building a new barrier.

There is some protection for households in frequently flooded areas; Under a joint government and industry program called Flood Re, insurers pay a fee to pool flood risks, allowing them to offer services to households at higher risk. This program applies to single-family homes rather than commercial properties and is scheduled to end in 2039, when climate-related flooding is expected to be more severe.

Dr Mark Andrew, of Bayes Business School, said insurance was likely to become more prohibitive, adding: “These pressures will intensify after the Flood Re program expires in 2039, when market-based pricing is expected to prevail. For residential properties, this creates a pronounced distributional challenge, as lower-income households are disproportionately concentrated in areas exposed to flooding and may not benefit from adequate coverage.”

Climate adaptation experts say this shows why flood insurance needs to be approached on a large scale rather than for individual properties.

Dr Carola Koenig from the Center for Flood Risk and Resilience at Brunel University London said: “Insurance needs to be approached collectively as a nation. Programs like Flood Re’s ‘build back better’ initiative enable businesses and homes to be better prepared for the future.”

She said homeowners and businesses should check their existing flood risks and “adapt their buildings, for example by installing flood doors, tiling floors or raising electrical outlets to ground level”.

Dr Jess Neumann, associate professor of hydrology at the University of Reading, said the government was not doing enough to protect people and businesses from flooding. “The future will require more investment, more support and more communication from government to help prepare people for flooding and manage impacts when the worst happens. »

She said traditional “hard engineering” approaches, such as sea walls, river defenses and flood barriers, which were still favored in many places, needed to be complemented by more nature-based solutions.

“We cannot continue to build higher and higher defenses to cope with greater and more frequent flooding. Working with natural processes, such as reconnecting rivers to their floodplains, restoring wetlands and planting wooded areas to intercept rainfall has the benefits of improving our natural environment while reducing flood risk.”